Costovertebral angle tenderness

Costovertebral angle tenderness (CVAT), also known as Murphy's punch sign or Pasternacki's sign or Goldflam's sign (Latin:succusio renalis), is a medical test in which pain is elicited by percussion of the area of the back overlying the kidney (the costovertebral angle, an angle made by the vertebral column and the costal margin). The test is positive in people with an infection around the kidney (perinephric abscess), pyelonephritis, hemorrhagic fever with renal syndrome or renal stone. Because the kidney lies directly below this area, known as the costovertebral angle, tapping disturbs the inflamed tissue, causing pain.